Method of treating ceramic mixtures



Patented Nov. 3, 1925.

7 UNITED STATES H ABR-Y SPURBIEB, OF. CHICAGO, ILLINOIS.

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methods of treating ceramic mixtures and more especially to thetreatment of bodies, notably of a plastic or porous character, and usedcommercially for the manufacture of pottery, crucibles, tile and stoneware, spark plugs, and the like.

The object of the invention is to provide an improved and more efficientmethod of rendering the body or plastic mass less vesicular, that is tosay, of decreased porosity by the removal of the air or gas content ofthe mass which is inherent therein.

It is well known in the ceramic art that it is desirable, if notessential that the mass be as and air free, in order that the resultmg"productsha'll' bensefiil forthe purpose intended.

I am not aware of any method heretofore develo d or in use at the resenttime 'which as successfully accom llshed the result contemplated by themet 0d herein described. I

While it is possible to accom lish the desired end in various ways, Iave discovered that the following is the most effective and therefore isto be preferred;

In describing the process it is to be understood that the term mass orbody contemplates an and all plastic or porous substances of w ich claymixed other ingredients, is a suita le example. Considering then a massof clay in plastic state it is a fact that it has gases d sseminatedthrou hout and which assume the form of glo ules, .some minute andothers of substantial size, dependin onthe circumstances and conditionsof t e mass. The problem therefore is to remove these gases and I havetherefore resorted to a process consisting of subjecting the mass toreduced air pressure, commonly conceived to be a vacuum.

This air pressure reduction 'or' the step termed evacuating the gasesfrom the mass, may be readily accomphshedbysigtroducing the mass to betreated into a perhaps with table air-' ap lication ma January 24, 1024.Serial No. 003,351.

tight chamber, having communication with an air exhausting ap aratussuch as an air pump and provide with one or more valved openings of asize to permit of a rapid im'ush of. air into the chamber when opened.By the action of the air pump, the air is exhausted as completely aspossible not only from the space (if any) surrounding the mass, but fromthe mass itself.

Having thus exhausted thegases from the mass by'the creation of thevacuum or condition of reduced air pressure, the vacuity is brokensuddenly by opening the inletsto the chamber so that the increase inpressure shall be as rapid as possible.

Assuming t at the inlets to the chamber communicate direct with theatmosphere, the pressure within the chamber is thus increased orrestoredto atmospheric pressure with a suddenness that results in thesub, jection of the mass to the attending impact which restores the sameto its initial condition, .with'the exception that the gases have beencompletely removed.

It is to be understood that in the practical application of the processcertain conditions may make it preferable to restore the pressure withinthe chamber to that of the atmosphere, whereas'under other conditions.better results may be obtained by introducin a pressure greater thanatmosheric in t ec amber after the evacuation as been completed. In thelatter instance any suitable means would be employed for supplying theincreased-air pressure to the chamber.

Having described the purpose, method of carrying out and results to beobtained by my process, I claim as my invention 1. The process oftreating ceramic mixtures consisting of evacuatin the gases from themass, and suddenly reaking the vacuum. 7

2. The process of treating ceramic masses consisting of evacuating thegases from the mass, and suddenly subjecting the mass to the materialinto a chamber, subjecting they a pressure equal to or greater than thatof a chamber to a relatively high vacuum and suddenly restoringthe'pressure within the chamber to substantially. atmospheric pres sure.a

5. The process of treatin ceramic materials consisting of introduclngthe material into a chamber, evacuating the gases in the chamber to arelatively high degree of vacuity, and suddenly breaking the vacuum,

without removing the material from the Q chamber. V g L In witnesswhereof, I hereuntw subscribe xlngy iname this 22nd day of January, A.D.,

' HARRY SPURRIER;

